package com.mqb.n8;

import com.mqb.n2.util.Sleeper;
import lombok.extern.slf4j.Slf4j;

import java.util.concurrent.locks.ReentrantReadWriteLock;

/**
 * @author mqb
 * @date 2021/5/3 16:46
 */
@Slf4j(topic = "c.TestReadWriteLock")
public class TestReadWriteLock {
    public static void main(String[] args) throws InterruptedException {
        DataContainer dc = new DataContainer();

        new Thread(()-> dc.read(),"t1").start();
        Thread.sleep(100);
        new Thread(()-> dc.write(),"t2").start();
    }
}

@Slf4j(topic = "c.DataContainer")
class DataContainer {
    private Object data;
    private ReentrantReadWriteLock rw = new ReentrantReadWriteLock();
    private ReentrantReadWriteLock.ReadLock r = rw.readLock();
    private ReentrantReadWriteLock.WriteLock w = rw.writeLock();

    public Object read() {
        log.debug("获取读锁");
        r.lock();
        try {
            log.debug("读取...");
            Sleeper.sleep(1);
            return data;
        } finally {
            log.debug("释放读锁");
            r.unlock();
        }
    }

    public void write() {
        log.debug("获取写锁");
        w.lock();
        try {
            log.debug("写入...");
        } finally {
            w.unlock();
        }
    }
}
